A turbine wastegate is typically a valve (e.g., a wastegate or wastegate valve) that can be controlled to selectively allow at least some exhaust to bypass a turbine. Where an exhaust gas of an internal combustion engine drives a turbine that can drive a compressor for boosting inlet pressure to an internal combustion engine (e.g., as in a turbocharger), a wastegate provides a means to control the boost pressure (e.g., by wastegating at least a portion of the exhaust gas).
A so-called internal wastegate can be characterized as being integrated at least partially into a turbine housing. An internal wastegate typically includes a flapper valve (e.g., a plug or poppet), a crank arm, a shaft or rod, and an actuator that can be coupled to a control linkage that is coupled to the crank arm, which may be considered a part of the control linkage. A plug of a wastegate often includes a flat disk shaped surface that seats against a flat seat (e.g., a valve seat or wastegate seat) disposed about an exhaust bypass opening, though various plugs may include a protruding portion that extends into an exhaust bypass opening (e.g., past a plane of a wastegate seat).
Wastegate components for various internal combustion engine applications may be of particular concern where operational temperatures and/or exhaust pulsation levels can be considerable. For example, noise may be generated responsive to exhaust pulsation and/or other vibration associated with operation of an internal combustion engine and/or a vehicle. Various examples of wastegates and wastegate related components, as are described herein, may provide for reduction in noise, etc.